CVE-2025-66471

CVE-2025-66471 is a high-severity resource exhaustion vulnerability affecting urllib3 versions 1.0 through 2.5.x. The flaw lies in the streaming API's improper handling of highly compressed data, where excessive CPU and memory can be consumed during decompression. With a CVSS score of 7.5 (High), this vulnerability can be exploited remotely with low attack complexity, leading to a denial-of-service (DoS) impact. While there is no known active exploitation or public exploit code, the vulnerability has garnered significant community discussion, with multiple mentions of fixes in GitHub and security advisories from vendors like SUSE.